Requirement for Interference and Carrier to Interference Ratio in GSM, carrier to interference, channel and adjacent, allowance in engineering.

Requirement for Interference and Carrier to Interference Ratio in GSM

GSM is an interference restricted system. Carrier-to-interference ratio (C/I), also called interference protection ratio, refers to the ratio of all useful signals to all useless signals.

In GSM system, this ratio is relevant to the instantaneous location and time of MS due to irregular landform, different shape, type and number of surrounding scatterer, different type, direction and height of antenna, as well as different number and intensity of interference source, etc.

Usually, the interference signal comes from the following three kinds of sources:

C/I refers to the interference from other cells to service cell when different cells use the same frequency. In a board sense, certainly the electromagnetic wave energy of all useless signals falling into this frequency carrier should also be considered.